com.vaadin.flow.component.polymertemplate

Class IdMapper

java.lang.Object

com.vaadin.flow.component.polymertemplate.IdMapper

All Implemented Interfaces:

Serializable

public class IdMapper
extends Object
implements Serializable

Creates or maps Element instances to fields mapped using @Id.

Since:

2.0

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
IdMapper(AbstractTemplate<?> template) Creates a mapper for the given template.

Method Summary

Modifier and Type	Method and Description
ShadowRoot	getOrCreateShadowRoot() Gets the shadow root for the template.
boolean	isMapped(String id) Checks if the given id has been mapped.
void	mapComponentOrElement(Field field, String id, String tag, Consumer<Element> beforeComponentInject) Maps an element or component to the given field.
void	reset() Resets the mapper to its original state, clearing any registered mappings.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

IdMapper

public IdMapper(AbstractTemplate<?> template)

Creates a mapper for the given template.

Parameters:

template - a template instance

Method Detail

mapComponentOrElement

public void mapComponentOrElement(Field field,
                                  String id,
                                  String tag,
                                  Consumer<Element> beforeComponentInject)

Maps an element or component to the given field.

If an element with the given id exists in the template element tree, that element is used.

If no element exists (the typical case), a virtual element is created and later on, when the template has been rendered in the client, is connected to the rendered element with the given id.

Parameters:

field - the field to assign the element/component to

id - the id of the element to map

tag - the tag of the injected element or null if not known

beforeComponentInject - a callback invoked before assigning the element/component to the field

getOrCreateShadowRoot

public ShadowRoot getOrCreateShadowRoot()

Gets the shadow root for the template.

Creates a shadow root if the template does not have one.

Returns:

the shadow root for the template

reset

public void reset()

Resets the mapper to its original state, clearing any registered mappings.

isMapped

public boolean isMapped(String id)

Checks if the given id has been mapped.

Parameters:

id - the id to check

Returns:

true if the element has been mapped, false otherwise